Photomask pattern inspection method and system and method of manufacturing display device using the same

Abstract

Disclosed are a photomask pattern inspection method and system and a method of manufacturing a display device using the same. The photomask pattern inspection method includes: generating first result image data by performing a first exposure simulation based on photomask design data; generating second result image data by performing a second exposure simulation based on optical image data obtained by photographing the actual photomask; and generating inspection data for the actual photomask based on the first result image data and the second result image data.

Description

[0001] This application claims priority to and all benefits derived from Korean Patent Application No. 10-2024-0014319, filed on January 30, 2024, the contents of which are incorporated herein by reference in their entirety. Technical Field

[0002] The embodiments relate to a photomask pattern inspection method and system and a method of manufacturing a display device using the same, and more particularly, to a photomask pattern inspection method and system capable of quickly inspecting a photomask pattern and a method of manufacturing a display device using the same. Background Art

[0003] The display device displays an image by receiving information about the image. The display device is used as a display for a small-sized product such as a mobile phone or a display for a large-sized product such as a television.

[0004] The circuits and wiring structures in display devices can be micropatterned. These micropatterns are formed through photolithography and etching processes. Photolithography uses a photomask with the micropattern. Therefore, for accurate display device processing, it is desirable to inspect the photomask pattern during the photomask manufacturing process. Summary of the Invention

[0005] The embodiments include a photomask pattern inspection method and system capable of quickly inspecting a photomask pattern. However, the embodiments are merely examples, and the scope of the present disclosure is not limited thereby.

[0006] Additional features will be set forth in part in the description which follows and, in part, will be apparent from the description, or may be learned by practice of the presented embodiments of the disclosure.

[0007] In an embodiment of the present disclosure, a photomask pattern inspection method may include: generating first result image data by performing a first exposure simulation based on photomask design data; generating second result image data by performing a second exposure simulation based on optical image data obtained by photographing an actual photomask; and generating inspection data for the actual photomask based on the first result image data and the second result image data.

[0008] In an embodiment, the photomask design data may be design data for an actual photomask.

[0009] In an embodiment, the generating of the first resultant image data may include generating the first resultant image data by performing a first exposure simulation based on pre-input exposure condition data and photomask design data.

[0010] In an embodiment, the generation of the second result image data may include generating the second result image data by performing a second exposure simulation based on pre-input exposure condition data and optical image data.

[0011] In an embodiment, the generation of inspection data for an actual photomask may include: generating a difference image between the first result image data and the second result image data; and generating inspection data based on the difference image.

[0012] In an embodiment, the generation of inspection data based on the difference image may include: when a feature value obtained from the difference image is greater than a preset threshold, defining the actual photomask as being in a defective state; and when the feature value is less than or equal to the preset threshold, defining the actual photomask as being in a normal state.

[0013] In an embodiment, the generation of the first result image data may include: loading the input exposure condition data and photomask design data; outputting a first exposure result image by performing a first exposure simulation based on the input exposure condition data and photomask design data; and generating the first result image data by correcting the first exposure result image.

[0014] In an embodiment, the generation of the first result image data by correcting the first exposure result image may include correcting the first exposure result image into a grayscale image having the same resolution as the second result image data.

[0015] In an embodiment, the generation of the second result image data may include: loading the input exposure condition data and receiving optical image data; performing a preprocessing process on the optical image data; after the preprocessing process, outputting a second exposure result image by performing a second exposure simulation based on the input exposure condition data and the optical image data; and generating the second result image data by correcting the second exposure result image.

[0016] In an embodiment, the execution of the preprocessing process on the optical image data may include: obtaining a contour image from the optical image data; and changing the resolution of the contour image to the resolution of the photomask design data.

[0017] In an embodiment of the present disclosure, a photomask pattern inspection system may include: an optical system device configured to generate optical image data for an actual photomask; and a computing device configured to: generate first result image data by performing a first exposure simulation based on pre-stored photomask design data; generate second result image data by performing a second exposure simulation based on the optical image data; and generate inspection data for the actual photomask based on the first result image data and the second result image data.

[0018] In an embodiment, the photomask design data may be design data for an actual photomask.

[0019] In an embodiment, the computing device may be configured to generate first result image data by performing a first exposure simulation based on pre-input exposure condition data and photomask design data.

[0020] In an embodiment, the computing device may be configured to generate second result image data by performing a second exposure simulation based on pre-input exposure condition data and optical image data.

[0021] In an embodiment, the computing device may be configured to: generate a difference image between the first result image data and the second result image data; and generate inspection data based on the difference image.

[0022] In an embodiment, the computing device may be configured to: when an eigenvalue derived from the difference image is greater than a preset threshold, define the actual photomask as being in a defective state; and when the eigenvalue is less than or equal to the preset threshold, define the actual photomask as being in a normal state.

[0023] In an embodiment, the computing device may be configured to: load the input exposure condition data and photomask design data; output a first exposure result image by performing a first exposure simulation based on the input exposure condition data and photomask design data; and generate first result image data by correcting the first exposure result image.

[0024] In an embodiment, the first exposure result image may be corrected into a grayscale image having the same resolution as that of the second result image data.

[0025] In an embodiment, the computing device may be configured to: load the input exposure condition data and receive optical image data; perform a preprocessing process on the optical image data; after the preprocessing process, output a second exposure result image by performing a second exposure simulation based on the input exposure condition data and the optical image data; and generate second result image data by correcting the second exposure result image.

[0026] In an embodiment, the computing device may be configured to: obtain a contour image from the optical image data; and change the resolution of the contour image to the resolution of the photomask design data.

[0027] In an embodiment of the present disclosure, a method of manufacturing a display device may include: checking a pattern of an actual photomask by a computing device; arranging the actual photomask on a target substrate when the pattern of the actual photomask is in a normal state; and performing an exposure process on the target substrate by the actual photomask. Wherein, the checking of the pattern of the actual photomask may include: generating first result image data by performing a first exposure simulation based on photomask design data; generating second result image data by performing a second exposure simulation based on optical image data obtained by photographing the actual photomask; and generating inspection data for the actual photomask based on the first result image data and the second result image data.

[0028] In an embodiment, the photomask design data may be design data for the actual photomask.

[0029] In an embodiment, the generation of the first result image data may include generating the first result image data by performing a first exposure simulation based on pre-input exposure condition data and photomask design data.

[0030] In an embodiment, the generation of the second result image data may include generating the second result image data by performing a second exposure simulation based on pre-input exposure condition data and optical image data.

[0031] In an embodiment, the generation of the inspection data for the actual photomask may include: generating a difference image between the first result image data and the second result image data; and generating inspection data based on the difference image. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The above and other features and advantages of the illustrative embodiments of the present disclosure will become more apparent from the following description taken in conjunction with the accompanying drawings, in which:

[0033] Figure 1 is a flowchart schematically illustrating an embodiment of a method for checking a photomask pattern;

[0034] Figure 2 is schematically illustrating the operation of Figure 1 generating the first result image data by performing a first exposure simulation;

[0035] Figure 3 is schematically illustrating the operation of Figure 1 generating the second result image data by performing a second exposure simulation;

[0036] Figure 4 is schematically illustrating Figure 1 the operation of generating inspection data;

[0037] Figure 5Ais a view schematically illustrating an embodiment of a photomask pattern inspection system, and Figure 5B is a view illustrating an actual photomask disposed on a target substrate;

[0038] Figure 6 is a view illustrating an embodiment of photomask design data for performing a first exposure simulation;

[0039] Figure 7 is a view illustrating an embodiment of a first exposure result image generated based on Figure 6 the photomask design data;

[0040] Figure 8 is a view illustrating an embodiment of first result image data generated based on Figure 7 the first exposure result image;

[0041] Figure 9 is a view illustrating an embodiment of optical image data obtained by photographing an actual photomask for performing a second exposure simulation;

[0042] Figure 10 is a view illustrating an embodiment of a contour image generated based on Figure 9 the optical image data;

[0043] Figure 11 is a view illustrating an embodiment of a second exposure result image generated based on Figure 10 the contour image; and

[0044] Figure 12 is a view illustrating an embodiment of second result image data generated based on Figure 11 the second exposure result image. DETAILED DESCRIPTION

[0045] Reference will now be made in detail to the embodiments, which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout the specification. In this regard, the illustrated embodiments may have different forms and should not be construed as limited to the description set forth herein. Accordingly, the embodiments are described only by referring to the accompanying drawings to explain the features of the specification. As used herein, the term "and / or" includes any combination and all combinations of one or more of the associated listed items. Throughout the present disclosure, the expression "at least one of a, b, and c" indicates only a, only b, only c, both a and b, both a and c, both b and c, all of a, b, and c, or variations thereof.

[0046] Various modifications can be applied to the illustrated embodiments, and specific embodiments of the present disclosure will be illustrated in the drawings and described in the detailed description section. The effects and features of the illustrated embodiments and the methods for implementing them will be more clearly understood with reference to the following detailed description in conjunction with the drawings. However, the present disclosure can be implemented in various forms without being limited to the embodiments presented below.

[0047] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings, and in the description with reference to the drawings, the same or corresponding components are denoted by the same reference numerals and redundant descriptions thereof are omitted.

[0048] In the following embodiments, it will be understood that when a component such as a layer, film, region, or plate is referred to as being "formed on" another layer, film, region, or plate, it can be formed directly or indirectly on the other layer, film, region, or plate. That is, for example, there may be intervening layers, films, regions, or plates. Additionally, in the following embodiments, it will be understood that when a component such as a layer, film, region, or plate is referred to as being "formed under" another layer, film, region, or plate, it can be formed directly or indirectly under the other layer, film, region, or plate. That is, for example, there may be intervening layers, films, regions, or plates.

[0049] For ease of explanation, the dimensions of components in the drawings may be exaggerated or reduced. In other words, since the dimensions and thicknesses of the components in the drawings are arbitrarily illustrated for ease of explanation, the following present disclosure is not limited thereto. That is, for ease of explanation, the dimensions, thicknesses, and ratios of the components in the drawings may be exaggerated and / or simplified for clarity. Accordingly, spatial relative terms such as "below", "beneath", "under", "underneath", "above", and "on" can be used to easily describe the relationship of one element or feature to another element or feature.

[0050] In the specification, it will be understood that terms used to describe space, direction, etc. are intended to include different directions or perspectives other than the space or direction shown in the drawings. For example, when the device or component in the drawing is flipped, the device described as "below" can be oriented in other ways (e.g., rotated 90 degrees or in the opposite direction). For example, when the device or component in the drawing is flipped, the device described as "above" can be oriented in other ways (e.g., rotated 90 degrees or in the opposite direction). Accordingly, the terms "below" and "above" can include both orientations of above and below. Additionally, the device or component can be oriented in other ways, and the spatial relative descriptors used herein should be interpreted accordingly.

[0051] In the specification, the process order or method order in the description of a process or manufacturing method may be different from the described order. For example, two consecutively described processes or methods may be performed substantially simultaneously or in an order opposite to the described order.

[0052] In the following embodiments, the x-axis, y-axis, and z-axis are not limited to the three axes of a rectangular coordinate system and may be interpreted in a broad sense. For example, the x-axis, y-axis, and z-axis may be perpendicular to each other, or may represent different directions that are not perpendicular to each other.

[0053] In the specification, the terms "first", "second", and "third" may be used to describe specific components, and the terms "first", "second", and "third" may be used to distinguish one component from another.

[0054] When a component is referred to as being "connected to" or "coupled to" another component, it may be directly connected to or directly coupled to that other component, or one or more intermediate components may be present therebetween.

[0055] Similarly, when a component is "electrically connected to" another component, the component and that other component may be directly and electrically connected or indirectly and electrically connected through a conductive component.

[0056] In addition, it will be understood that when a component is referred to as being "between" two components, it is the only component disposed between the two components, or intermediate components other than that component are disposed between the two components.

[0057] The terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the present disclosure. Unless the context clearly indicates otherwise, the singular term "a" used herein is also intended to include the plural form.

[0058] For example, the terms "comprising", "including", and their variants specify the presence of the described features, wholes, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, wholes, steps, operations, elements, components, and / or groups thereof.

[0059] For example, the term "and / or" includes any combination and all combinations of one or more of the related listed items. For example, the expression "A and / or B" indicates A, B, or A and B. The expression "at least one of..." may be used to indicate one or more of a plurality of components. For example, the expression "at least one of a, b, and c" or "at least one selected from the group consisting of a, b, and c" may indicate "a", "b", "c", "a, b", "b, c", "a, c", or "a, b, c".

[0060] For example, terms such as "substantially" and "about" and similar terms are used as approximate terms rather than terms of degree, and can be intended to account for the inherent deviations in the values being measured or calculated that would be recognized by a person of ordinary skill in the art. For example, the use of the term "may" or "can" in describing an embodiment can refer to an embodiment disclosed in the specification.

[0061] The electronic or electrical devices and / or other related devices or components (e.g., some of the various modules) in the embodiments described herein can be implemented by any suitable hardware, firmware (e.g., application specific integrated circuit), software, or a combination of software, firmware, and hardware. In an embodiment, the various components of these devices can be formed on one integrated circuit ("IC") chip or multiple separate IC chips. Additionally, the various components of these devices can be formed on a flexible printed circuit film, tape carrier package ("TCP"), printed circuit board ("PCB"), or formed on a substrate. Further, the various components of these devices can be processes or threads that run on one or more processors in one or more computing devices, execute computer program instructions, and interact with other system components to perform the various functions described herein.

[0062] The computer program instructions are stored in a memory that can be implemented in a computing device using a standard memory device such as random access memory ("RAM"). The computer program instructions can also be stored in other non-transitory computer-readable media (such as a compact disc read-only memory ("CD-ROM") or a flash drive). Additionally, those of ordinary skill in the art should recognize that the functions of various computing devices can be combined or integrated into a single computing device, or the functions of a given computing device can be distributed across one or more other computing devices without departing from the spirit and scope of the embodiments.

[0063] Hereinafter, the photomask pattern inspection method and system in the embodiments will be described in detail based on the above description.

[0064] For reference, the subject that executes the photomask pattern inspection method mentioned herein can be a computing device or a processor of a computing device, which will be described later.

[0065] Figure 1 is a flowchart schematically illustrating an embodiment of the photomask pattern inspection method.

[0066] As Figure 1 shown, the photomask pattern inspection method in the embodiment can include generating first result image data by performing a first exposure simulation based on photomask design data (operation S1100).

[0067] The photomask design data can be the design drawing of the photomask. In other words, the photomask design data is the design data for the actual photomask. In an embodiment, for example, the photomask design data can be a Graphic Database System ("GDS") or an Open Artwork System Interchange Standard ("OASIS") file, etc., and when the photomask includes multiple layers, the photomask design data can be layer-specific design drawings.

[0068] The first exposure simulation can be performed based on pre-input exposure condition data and photomask design data. For example, the pre-input exposure condition data can include conditions regarding the wavelength of the light source, the intensity of the light, the coherence of the light, the area of exposure, etc. The pre-input exposure condition data is a value input by the user and can be stored in a memory.

[0069] The first exposure simulation can virtually perform an exposure process on the photomask design data under the pre-input exposure conditions. In an embodiment, the simulation tool for virtually performing the exposure process can be existing commercial software such as Synopsis etc. The first exposure simulation can obtain the pattern state after the etching process following the exposure process.

[0070] In an embodiment, for example, the first exposure result image can be the result value obtained through the first exposure simulation. The first exposure simulation performed on the photomask design data under the pre-input exposure conditions can generate a first exposure result image generated according to the pattern of the photomask design data. The first result image data can be generated from the first exposure result image.

[0071] The photomask pattern inspection method in the embodiment can further include generating second result image data (operation S1200) by performing a second exposure simulation based on optical image data obtained by photographing an actual photomask.

[0072] The actual photomask is expected for the exposure process and can be used in the actual process. The actual photomask can be manufactured based on the photomask design data.

[0073] The optical image data can be obtained by an optical system device. In an embodiment, for example, the optical system device can include a light source disposed on one side of the actual photomask and an image sensor disposed in a direction opposite to the light source with respect to the actual photomask. In an embodiment, the optical image data can be obtained by photographing the actual photomask by the optical system device.

[0074] The second exposure simulation can be implemented via the same software as the software for the first exposure simulation. The second exposure simulation can be performed based on the pre-input exposure condition data (also referred to as the input exposure condition data for convenience hereinafter) and the optical image data.

[0075] The exposure conditions for the second exposure simulation input can be the same as those for the first exposure simulation input. In an embodiment, for example, the pre-input exposure condition data may include conditions regarding the wavelength of the light source, the intensity of the light, the coherence of the light, the area of exposure, etc. The pre-input exposure condition data is a value input by the user and can be stored in a memory.

[0076] The second exposure simulation can virtually perform an exposure process on the optical image data under the pre-input exposure conditions. In an embodiment, the simulation tool for virtually performing the exposure process can be existing commercial software such as Synopsis and the like. The second exposure simulation can obtain the pattern state after the etching process following the exposure process.

[0077] In an embodiment, for example, the second exposure result image can be the result value obtained through the second exposure simulation. The second exposure simulation performed on the optical image data under the pre-input exposure conditions can generate a second exposure result image generated according to the pattern of the optical image data. The second result image data can be generated from the second exposure result image.

[0078] The photomask pattern inspection method in the embodiment may further include generating inspection data for the actual photomask based on the first result image data and the second result image data (operation S1300).

[0079] The inspection data can be generated based on a differential image (generated based on the first result image and the second result image), and can include information on whether the eigenvalue obtained from the differential image is greater than a preset threshold.

[0080] In an embodiment, for example, when the eigenvalue obtained from the differential image is greater than the preset threshold, the inspection data may include information indicating that the actual photomask is in a defective state. In an embodiment, for example, when the eigenvalue obtained from the differential image is less than or equal to the preset threshold, the inspection data may include information indicating that the actual photomask is in a normal state.

[0081] Similarly, according to the photomask pattern inspection method in the embodiment, during the operation of manufacturing a photomask, quick and accurate inspection is possible. The photomask pattern inspection method in the embodiment can perform the first exposure simulation in advance, or can perform the first exposure simulation in parallel with the second exposure simulation. Although it is possible to perform the inspection of the photomask pattern by means of the optical system device for implementing the projection optical system, when the photomask pattern inspection is performed only by this device, due to differences in the lens, light source, mechanism, actual exposure environment, etc. of the optical system device, an error may occur between the exposure result in the actual display manufacturing process and the exposure result during the inspection. In order to minimize the occurrence of such an error and perform a quick inspection, the present disclosure performs two simulations and performs pattern inspection by means of the differential image of the two simulation results.

[0082] In addition, the organic light emitting display device adopts a current driving method, and the current driving method is more accurate and better in terms of distribution than other driving methods. Therefore, accurate inspection of the photomask pattern is important.

[0083] Figure 2 is a flowchart schematically illustrating the operation of generating first result image data by performing Figure 1 the first exposure simulation.

[0084] As Figure 2 shown, the generation of the first result image data by performing the first exposure simulation (operation S1100) may include loading the input exposure condition data and the photomask design data (operation S1110).

[0085] The exposure condition data input by the user may be stored in a computing device described later. In addition, the photomask design data may also be stored in a computing device described later. Therefore, the generation of the first result image data by performing the first exposure simulation (operation S1100) may include loading the exposure condition data and the photomask design data stored (or pre-input) in a computing device described later to perform the first exposure simulation.

[0086] The generation of the first result image data by performing the first exposure simulation (operation S1100) may further include outputting a first exposure result image by performing the first exposure simulation based on the input exposure condition data and the photomask design data (operation S1120) and generating the first result image data by correcting the first exposure result image (operation S1130).

[0087] As a result of the simulation, the first exposure result image may be an image showing light that has undergone diffraction and interference according to the photomask design data. The generation of the first result image data by correcting the generation of the first exposure result image (operation S1130) may include correcting the first exposure result image into a grayscale image having the same resolution as the second result image data. In an embodiment, for example, the first result image data may be obtained by converting the first exposure result image into a grayscale image. Additionally, the first result image data may be obtained by changing the resolution of the first exposure result image to a predetermined resolution (e.g., the same resolution as the second result image data). The first result image data may be a spatial image of the image data whose resolution has been changed. The spatial image may have a size determined by the result of optimizing cable transmission speed, memory, and storage high-speed read / write (“R / W”) capabilities and / or central processing unit (“CPU”) computational complexity.

[0088] Figure 3 is schematically illustrated by performing Figure 1 the second exposure simulation to generate the second result image data.

[0089] As Figure 3 shown, the generation of the second result image data by performing the second exposure simulation (operation S1200) may include loading the input exposure condition data and receiving the optical image data (operation S1210).

[0090] The generation of the second result image data by performing the second exposure simulation (operation S1200) may further include performing a preprocessing process on the optical image data (operation S1220). The execution of the preprocessing process on the optical image data (operation S1220) may include obtaining a contour image from the optical image data and changing the resolution of the contour image to the resolution of the photomask design data.

[0091] In an embodiment, for example, the preprocessing process may include at least some of the processes of removing noise from the optical image data, obtaining a contour image of the optical image data, changing the resolution of the contour image to the resolution of the photomask design data, and removing artifacts that appear when changing the resolution (e.g., magnifying).

[0092] The generation of the second result image data by performing the second exposure simulation (operation S1200) may further include: after the preprocessing process, outputting a second exposure result image by performing a second exposure simulation based on the pre-input exposure condition data and the optical image data (operation S1230); and generating the second result image data by correcting the second exposure result image (operation S1240).

[0093] The second exposure result image can be captured by an optical system device and can be an image showing light that has undergone diffraction and interference according to the pattern of the actual photomask. The generation of the second result image data by correcting the generation of the second exposure result image (operation S1240) can include correcting the second exposure result image into a grayscale image having the same resolution as the first result image data. In an embodiment, for example, the second result image data can be obtained by converting the second exposure result image into a grayscale image. Additionally, the second result image data can be obtained by changing the resolution of the second exposure result image to a predetermined resolution (e.g., the same resolution as the first result image data). The second result image data can be a spatial image of the image data whose resolution has been changed. The spatial image can have dimensions determined by the result of optimizing cable transmission speed, memory, and storage high-speed R / W capabilities and / or CPU computing complexity.

[0094] Additionally, the correction of the second exposure result image can be performed by a neural network model. In an embodiment, the neural network model for image correction can be a generative adversarial network (“GAN”) model, a neural style transfer model, etc. In some cases, for example, the neural network model for image correction can be a commercial model such as a rigorous simulation model, an inverse lithography technology (“ILT”) model, etc. The method for improving resolution can be interpolation, image super-resolution, etc.

[0095] Figure 4 is schematically illustrated Figure 1 a flowchart of the operation of generating inspection data.

[0096] As Figure 4 shown, the generation of inspection data for the actual photomask (operation S1300) can include generating a difference image between the first result image data and the second result image data (operation S1310).

[0097] The difference image can refer to the difference between the first result image data and the second result image data. To generate the difference image, the first result image data and the second result image data can be corrected to the same standard (e.g., the same resolution, grayscale image, etc.).

[0098] The generation of inspection data for the actual photomask (operation S1300) can further include generating inspection data based on the difference image (operation S1320). The generation of inspection data based on the difference image (operation S1320) can include: when the eigenvalue (e.g., gray level, size level, etc.) obtained from the difference image is greater than a preset threshold, defining the actual photomask as being in a defective state; and when the eigenvalue (e.g., gray level, size level, etc.) is less than or equal to the preset threshold, defining the actual photomask as being in a normal state.

[0099] The generation of inspection data for an actual photomask (operation S1300) may include: performing blob analysis on differential pixels greater than a threshold set by a user in a differential image; and generating or outputting inspection data based on the results of the blob analysis. The blob analysis can obtain size information, type information, etc., which are the results of the blob analysis of the differential image. Tools for blob analysis can be software known conventionally. The generation of inspection data for an actual photomask (operation S1300) may include generating a defect file including coordinates, serial numbers, etc. of defective areas in the differential image.

[0100] Figure 5A is a view schematically illustrating an embodiment of a photomask pattern inspection system, and Figure 5B is a view illustrating an actual photomask disposed on a target substrate.

[0101] For reference, in Figure 5A and Figure 5B the description of the photomask pattern inspection system, the description already provided with reference to Figures 1 to 4 may not be provided.

[0102] As Figure 5A shown, the photomask pattern inspection system in the embodiment may include an optical system device 100 and a computing device 200.

[0103] The optical system device 100 may generate optical image data for the actual photomask 10. The optical system device 100 may include a light source 110, a condenser lens 120, an objective lens 130, a tube lens 140, and an automatic optical inspection (“AOI”) camera 150.

[0104] In the embodiment, for example, the light source 110 may be disposed on one side of the actual photomask 10. The condenser lens 120 may be arranged between the light source 110 and the actual photomask 10. The light source 110 may irradiate light (e.g., ultraviolet light) toward the condenser lens 120, and the light reflected by the condenser lens 120 may pass through the actual photomask 10 and be guided to the objective lens 130. The light that has passed through the objective lens 130 and the tube lens 140 may be guided to the AOI camera 150, and the AOI camera 150 may generate optical image data for the actual photomask 10. The generated optical image data may be transmitted to the computing device 200.

[0105] The computing device 200 may generate first result image data by performing a first exposure simulation based on pre-stored photomask design data. The computing device 200 may generate second result image data by performing a second exposure simulation based on optical image data. The computing device 200 may generate inspection data for the actual photomask 10 based on the first result image data and the second result image data.

[0106] The computing device 200 may include a processor 210, a memory 220, and a data transceiver 230. The processor 210 may control other components by executing instructions stored in the memory 220. The processor 210 may execute instructions stored in the memory 220.

[0107] The processor 210 may be a component capable of performing calculations and controlling other devices. Primarily, the processor 210 may refer to a CPU, an application processor (“AP”), a graphics processing unit (“GPU”), etc. Additionally, the CPU, AP, or GPU may include at least one core therein, and the CPU, AP, or GPU may operate through an operating voltage and a clock signal.

[0108] The processor 210 may process or provide appropriate information or functions to the user by processing signals, data, information, etc. input or output through the above components or by driving application programs stored in the memory 220.

[0109] The memory 220 stores data supporting various functions of the computing device 200. The memory 220 may store multiple application programs (or apps) running on the computing device 200, data for operating the computing device 200, and instructions.

[0110] The memory 220 may include at least one type of storage medium among flash type, hard disk type, solid state drive (“SSD”) type, silicon disk drive (“SDD”) type, multimedia card micro, card type memory (e.g., secure digital (“SD”) or extreme digital (“XD”) memory, etc.), random access memory (“RAM”), static RAM (“SRAM”), read only memory (“ROM”), electrically erasable programmable ROM (“EEPROM”), programmable ROM (“PROM”), magnetic memory, magnetic disks, and optical disks.

[0111] The data transceiver 230 may perform a wired communication function or wireless communication. The wireless communication may be communication using a wireless communication network (using communication facilities previously installed by a communication company and the frequencies of these communication facilities) (e.g., third generation (“3G”), long term evolution (“LTE”), fifth generation (“5G”), sixth generation (“6G”), etc.), or may be such as Short-range communications such as low energy ("BLE"), beacons, radio frequency identification ("RFID"), near field communication ("NFC"), Infrared Data Association ("IrDA"), ultra-wideband ("UWB"), and the global standard for regional interoperability ("ZigBee").

[0112] The computing device 200 can generate first result image data by performing a first exposure simulation based on the photomask design data. The first exposure simulation can be performed based on the pre-input exposure condition data and the photomask design data. For example, the pre-input exposure condition data can include conditions regarding the wavelength of the light source 110, the intensity of the light, the coherence of the light, the area of the exposure, etc. The pre-input exposure condition data is a value input by the user and can be stored in the memory 220.

[0113] In an embodiment, for example, the first result image data can be the result value obtained from the first exposure simulation. The first exposure simulation performed on the photomask design data under the pre-input exposure conditions can generate exposure image data generated according to the pattern of the photomask design data. The first result image data can be the spatial image of the generated exposure image data.

[0114] The computing device 200 can generate second result image data by performing a second exposure simulation based on the optical image data obtained by photographing the actual photomask 10. The actual photomask 10 is desired for the exposure process and can be used in the actual process. The actual photomask 10 can be manufactured based on the photomask design data.

[0115] The exposure conditions input for the second exposure simulation can be the same as those input for the first exposure simulation. In an embodiment, for example, the pre-input exposure condition data can include conditions regarding the wavelength of the light source 110 (e.g., ultraviolet band), the intensity of the light, the coherence of the light, the area of the exposure, etc. The pre-input exposure condition data is a value input by the user and can be stored in the memory 220.

[0116] The second exposure simulation can virtually perform an exposure process on the optical image data under the pre-input exposure conditions. In an embodiment, for example, the second result image data can be the result value obtained from the second exposure simulation. The second exposure simulation performed on the optical image data under the pre-input exposure conditions can generate exposure image data generated according to the pattern of the optical image data. The second result image data can be the spatial image of the generated exposure image data.

[0117] The computing device 200 may generate inspection data for the actual photomask 10 based on the first result image data and the second result image data. The inspection data may be generated based on a differential image (generated based on the first result image and the second result image), and may include information on whether a feature value derived from the differential image is greater than a preset threshold value.

[0118] In an embodiment, for example, when the feature value derived from the differential image is greater than the preset threshold value, the inspection data may include information indicating that the actual photomask 10 is in a defective state. In an embodiment, for example, when the feature value derived from the differential image is less than or equal to the preset threshold value, the inspection data may include information indicating that the actual photomask 10 is in a normal state.

[0119] The computing device 200 may store exposure condition data and photomask design data. Thus, the computing device 200 may load the input exposure condition data and photomask design data to generate the first result image data by performing a first exposure simulation.

[0120] The computing device 200 may output a first exposure result image by performing a first exposure simulation based on the input exposure condition data and photomask design data, and generate the first result image data by correcting the first exposure result image.

[0121] As a result of the simulation, the first exposure result image may be an image showing light that has undergone diffraction and interference according to the photomask design data. The computing device 200 may correct the first exposure result image into a grayscale image having the same resolution as the second result image data. In an embodiment, for example, the first result image data may be obtained by converting the first exposure result image into a grayscale image. Additionally, the first result image data may be obtained by changing the resolution of the first exposure result image to a predetermined resolution (e.g., the same resolution as the second result image data). The first result image data may be a spatial image of the image data whose resolution has been changed. The spatial image may have dimensions determined by the result of optimizing cable transmission speed, memory, and storage high-speed R / W capabilities, as well as CPU computing complexity.

[0122] The computing device 200 may load the input exposure condition data and receive optical image data. The computing device 200 may perform a preprocessing process on the optical image data.

[0123] The preprocessing process performed by the computing device 200 may include a process of obtaining a contour image from the optical image data and a process of changing the resolution of the contour image to the resolution of the photomask design data.

[0124] In an embodiment, for example, the computing device 200 may perform a preprocessing process including at least some of the processes of removing noise from the optical image data, obtaining a contour image of the optical image data, changing the resolution of the contour image to the resolution of the photomask design data, and removing artifacts that appear when changing the resolution (e.g., magnifying).

[0125] After the preprocessing process, the computing device 200 may output a second exposure result image by performing a second exposure simulation based on pre-input exposure condition data and optical image data, and generate second result image data by correcting the second exposure result image.

[0126] The second exposure result image may be captured by the optical system device 100 and may be an image showing light that has undergone diffraction and interference according to the pattern of the actual photomask 10. The computing device 200 may correct the second exposure result image to a grayscale image having the same resolution as the first result image data. In an embodiment, the second result image data may be obtained by converting the second exposure result image into a grayscale image. Additionally, for example, the second result image data may be obtained by changing the resolution of the second exposure result image to a predetermined resolution (e.g., the same resolution as the first result image data). The second result image data may be a spatial image of the image data whose resolution has been changed. The spatial image may have a size determined by the result of optimizing the cable transmission speed, memory, and storage high-speed R / W capabilities, and the CPU computing complexity.

[0127] Additionally, the computing device 200 may drive or use a neural network model to correct the second exposure result image. In an embodiment, the neural network model for image correction may be a GAN model, a style transfer model, etc. In some cases, for example, the neural network model for image correction may be a commercial model including rigorous simulation (FDTD, etc.) or compact simulation (TCC, TMM, etc.) or a commercial model such as ILT.

[0128] The computing device 200 may generate a difference image between the first result image data and the second result image data. The difference image may refer to the difference between the first result image data and the second result image data. To generate the difference image, the first result image data and the second result image data may be corrected to the same standard (e.g., the same resolution, grayscale image, etc.).

[0129] The computing device 200 may generate inspection data based on the differential image. When the eigenvalue (e.g., gray level, size level, etc.) obtained from the differential image is greater than a preset threshold, the computing device 200 may define the actual photomask 10 as being in a defective state, and when the eigenvalue (e.g., gray level, size level, etc.) is less than or equal to the preset threshold, define the actual photomask 10 as being in a normal state.

[0130] The computing device 200 may perform blob analysis (and binarization) of the differential pixels in the differential image that are greater than the threshold set by the user, and generate or output inspection data through the result of the blob analysis. The blob analysis may obtain size information, type information, etc. of the object detected in the differential image. The tool for blob analysis may be software known in the art. The computing device 200 may generate a defect file including the coordinates, serial numbers, etc. of the blob regions in the differential image.

[0131] Similarly, according to the photomask pattern inspection system in the embodiment, during the operation of manufacturing the photomask, fast and accurate inspection is possible. Although it is possible to perform the inspection of the photomask pattern only through the optical system device 100, when the inspection of the photomask pattern is performed only through the optical system device 100, due to the differences in the lenses, light source 110, mechanisms, etc. of the optical system device 100, an error may occur between the exposure result in the actual display manufacturing process and the exposure result during the inspection. In order to minimize the occurrence of such an error and perform a fast inspection, the present disclosure pre-performs the first exposure simulation through the computing device 200 or performs the first exposure simulation in parallel with the second exposure simulation, and performs pattern inspection through the differential image of the two simulation results.

[0132] In addition, the organic light-emitting display device adopts a current driving method, and the current driving method is more accurate and better in terms of distribution than other driving methods. Therefore, accurate inspection of the photomask pattern is important.

[0133] Figure 6 FIG. is a view showing an embodiment of the photomask design data for performing the first exposure simulation.

[0134] Refer to Figure 6 , the photomask design data may be a design drawing of the actual photomask 10. The photomask design data may include a transmissive region through which light (e.g., ultraviolet light) can pass during exposure and a non-transmissive region through which light cannot pass. The photomask design data may be a design drawing of the exposure pattern according to the shapes of the transmissive region and the non-transmissive region.

[0135] Figure 7 FIG. is a view showing an embodiment of the first exposure result image generated based on the Figure 6 photomask design data.

[0136] Reference Figure 7 The first exposure result image may be the result data of the first exposure simulation. The first exposure result image may be the result data of the first exposure simulation in the case of irradiating light (for example, ultraviolet light) under the exposure conditions that have been previously input into the photomask design data. The degree of diffraction, interference, and transmission of light can be simulated according to the pattern of the photomask design data, and in the first exposure result image, the degree of diffraction, interference, and transmission of light can be represented by colors, grayscale, etc.

[0137] Figure 8 is a view showing an embodiment of the first result image data generated based on Figure 7 the first exposure result image.

[0138] Reference Figure 8 The first result image data may be an image obtained by correcting the first exposure result image. In an embodiment, for example, the first result image data may be an image obtained by correcting the first exposure result image to have the same resolution as the second result image data. In an embodiment, for example, the first result image data may be an image obtained by correcting the first exposure result image to a grayscale image.

[0139] Figure 9 is a view showing an embodiment of the optical image data obtained by photographing the actual photomask for performing the second exposure simulation.

[0140] Reference Figure 9 The optical image data is an image generated by the optical system device 100 and may be an image of the actual photomask 10. The actual photomask 10 is generated based on the photomask design data, and the optical image data may have the same or similar pattern as the photomask design data.

[0141] Figure 10 is a view showing an embodiment of the contour image generated based on Figure 9 the optical image data.

[0142] Reference Figure 10 The contour image is generated from the optical image data and may include the boundary lines of the pattern for the actual photomask 10. The contour image may correspond to the photomask design data.

[0143] Figure 11 is a view showing an embodiment of the second exposure result image generated based on Figure 10 the contour image.

[0144] Reference Figure 11, the computing device 200 may obtain pattern information including the transmissive and non-transmissive regions of the photomask based on the optical image data and the contour image. Accordingly, the second exposure result image may be the result data of the second exposure simulation. The second exposure result image may be the result data of the second exposure simulation in a case where light (e.g., ultraviolet light) is irradiated under the exposure conditions that have been previously input into the pattern information obtained based on the optical image data and the contour image).

[0145] In the second exposure result image, the degree of diffraction, interference, and transmission of light may be simulated according to the pattern information obtained based on the optical image data and the contour image, and in the second exposure result image, the degree of diffraction, interference, and transmission of light may be represented by color, grayscale, etc.

[0146] Figure 12 is a view showing an embodiment of the second result image data generated based on Figure 11 the second exposure result image.

[0147] Referring to Figure 12 , the second result image data may be an image obtained by correcting the second exposure result image. In an embodiment, for example, the second result image data may be an image obtained by correcting the second exposure result image to have the same resolution as the first result image data. In an embodiment, for example, the second result image data may be an image obtained by correcting the second exposure result image into a grayscale image.

[0148] In addition, based on the description provided above, a detailed description of a method of manufacturing a display device by the photomask pattern inspection method and system in an embodiment (hereinafter, also referred to as a method of manufacturing a display device) is as follows.

[0149] The method of manufacturing a display device in an embodiment may include: inspecting the pattern of the actual photomask 10 by Figure 5A the computing device 200; when Figure 5A the pattern of the actual photomask 10 is in a normal state, disposing the actual photomask 10 on Figure 5B the target substrate 20; and performing an exposure process on the target substrate 20 through the actual photomask 10. In an embodiment, the actual photomask 10 is directly disposed on the target substrate 20, but the present disclosure is not limited thereto, and the actual photomask 10 may be spaced apart from the target substrate 20.

[0150] The normal state is information included in the inspection data and may refer to a case where the eigenvalue of the differential image is less than or equal to a preset threshold.

[0151] The target substrate 20 may refer to a target on which a pattern is formed by the actual photomask 10. For ease of explanation, the term "target substrate" may be used, but may refer to all components or layers on which a pattern may be formed in a display device.

[0152] The inspection of the pattern of the actual photomask 10 by the computing device 200 may refer to the photomask pattern inspection method described with reference to Figures 1 to 4 Therefore, the description of the inspection of the pattern of the actual photomask 10 by the computing device 200 has been provided above with reference to Figures 1 to 4 and is thus not provided again.

[0153] In an embodiment, a photomask pattern inspection method and system capable of quickly inspecting a photomask pattern and a method of manufacturing a display device through the photomask pattern inspection method and system may be implemented. However, the scope of the present disclosure is not limited by this effect.

[0154] It should be understood that the embodiments described herein should be considered only in a descriptive sense and not for purposes of limitation. The description of features or advantages within each embodiment should generally be considered available for other similar features or advantages in other embodiments. Although the embodiments have been described with reference to the drawn figures, those of ordinary skill in the art will understand that various changes in form and detail may be made therein without departing from the spirit and scope as defined by the claims.

Claims

1. A method for inspecting a photomask pattern, comprising: Generating first result image data by performing a first exposure simulation based on photomask design data; Generating second result image data by performing a second exposure simulation based on optical image data obtained by photographing an actual photomask; And Generating inspection data for the actual photomask based on the first result image data and the second result image data.

2. The photomask pattern inspection method according to claim 1, wherein, The photomask design data is design data for the actual photomask.

3. The photomask pattern inspection method according to any one of claims 1 and 2, wherein The generation of the first result image data includes generating the first result image data by performing the first exposure simulation based on pre-input exposure condition data and the photomask design data.

4. The photomask pattern inspection method according to claim 3, wherein, The generation of the second result image data includes generating the second result image data by performing the second exposure simulation based on the pre-input exposure condition data and the optical image data.

5. The photomask pattern inspection method according to claim 4, wherein, The generation of the inspection data for the actual photomask includes: Generating a difference image between the first result image data and the second result image data; and Generating the inspection data based on the difference image.

6. The photomask pattern inspection method according to claim 5, wherein, The generation of the inspection data based on the difference image includes: When a feature value obtained from the difference image is greater than a preset threshold, defining the actual photomask as being in a defective state; and When the feature value is less than or equal to the preset threshold, defining the actual photomask as being in a normal state.

7. The photomask pattern inspection method according to any one of claims 1 and 2, wherein, The generation of the first result image data includes: Loading the input exposure condition data and the photomask design data; Outputting a first exposure result image by performing the first exposure simulation based on the input exposure condition data and the photomask design data; and Generating the first result image data by correcting the first exposure result image.

8. The photomask pattern inspection method according to claim 7, wherein, The generation of the first result image data by correcting the first exposure result image includes correcting the first exposure result image into a grayscale image having the same resolution as the second result image data.

9. The photomask pattern inspection method according to any one of claims 1 and 2, wherein, The generation of the second result image data includes: Loading the input exposure condition data and receiving the optical image data; Performing a preprocessing process on the optical image data; After the preprocessing process, outputting a second exposure result image by performing the second exposure simulation based on the input exposure condition data and the optical image data; and Generating the second result image data by correcting the second exposure result image.

10. The photomask pattern inspection method according to claim 9, wherein, The performing of the preprocessing process on the optical image data includes: Obtaining a contour image from the optical image data; and Changing the resolution of the contour image to the resolution of the photomask design data.

11. A photomask pattern inspection system, comprising: An optical system device configured to generate optical image data for an actual photomask; And A computing device configured to: Generate first result image data by performing a first exposure simulation based on pre-stored photomask design data; Generating second result image data by performing a second exposure simulation based on the optical image data; and Generating inspection data for the actual photomask based on the first result image data and the second result image data.

12. The photomask pattern inspection system according to claim 11, wherein, The photomask design data is design data for the actual photomask.

13. The photomask pattern inspection system according to any one of claims 11 and 12, wherein, The computing device is configured to generate the first result image data by performing the first exposure simulation based on pre-input exposure condition data and the photomask design data.

14. The photomask pattern inspection system according to claim 13, wherein, The computing device is configured to generate the second result image data by performing the second exposure simulation based on the pre-input exposure condition data and the optical image data.

15. The photomask pattern inspection system according to claim 14, wherein, The computing device is configured to: Generate a difference image between the first result image data and the second result image data; and Generate the inspection data based on the difference image.

16. The photomask pattern inspection system according to claim 15, wherein, The computing device is configured to: When a feature value obtained from the difference image is greater than a preset threshold, define the actual photomask as being in a defective state; and When the feature value is less than or equal to the preset threshold, define the actual photomask as being in a normal state.

17. The photomask pattern inspection system according to any one of claims 11 and 12, wherein The computing device is configured to: Load the input exposure condition data and the photomask design data; Output a first exposure result image by performing the first exposure simulation based on the input exposure condition data and the photomask design data; and Generate the first result image data by correcting the first exposure result image.

18. The photomask pattern inspection system according to claim 17, wherein, The first exposure result image is corrected into a grayscale image having the same resolution as the second result image data.

19. The photomask pattern inspection system according to any one of claims 11 and 12, wherein, The computing device is configured to: Load the input exposure condition data and receive the optical image data; Perform a preprocessing process on the optical image data; After the preprocessing process, output a second exposure result image by performing the second exposure simulation based on the input exposure condition data and the optical image data; and Generate the second result image data by correcting the second exposure result image.

20. The photomask pattern inspection system according to claim 19, wherein, The computing device is configured to: Obtain a contour image from the optical image data; and Change the resolution of the contour image to the resolution of the photomask design data.

21. A method of manufacturing a display device, the method comprising: Inspecting a pattern of an actual photomask by a computing device; When the pattern of the actual photomask is in a normal state, arranging the actual photomask on a target substrate; Performing an exposure process on the target substrate by the actual photomask, wherein the inspection of the pattern of the actual photomask includes: Generating first result image data by performing a first exposure simulation based on photomask design data; Generating second result image data by performing a second exposure simulation based on optical image data obtained by photographing the actual photomask; and Generating inspection data for the actual photomask based on the first result image data and the second result image data.

22. The method according to claim 21, wherein The photomask design data is design data for the actual photomask.

23. The method according to any one of claims 21 and 22, wherein, The generation of the first result image data includes generating the first result image data by performing the first exposure simulation based on pre-input exposure condition data and the photomask design data.

24. The method according to claim 23, wherein, The generation of the second result image data includes generating the second result image data by performing the second exposure simulation based on the pre-input exposure condition data and the optical image data.

25. The method according to claim 24, wherein The generation of the inspection data for the actual photomask includes: generating a difference image between the first result image data and the second result image data; and generating the inspection data based on the difference image.

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